Application: kwin_x11 (5.3.0)

Qt Version: 5.4.1
Operating System: Linux 4.0.4-303.fc22.x86_64 x86_64
Distribution: "Fedora release 22 (Twenty Two)"

-- Information about the crash:
- What I was doing when the application crashed:

The crash happens sometimes, just after log in.

GLobally, the whole plasma 5 is unstable. I also experience arbitrary Xorg freezes, obliging me to reboot.

The crash can be reproduced sometimes.

-- Backtrace:
Application: KWin (kwin_x11), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
[Current thread is 1 (Thread 0x7fddb53e3900 (LWP 1940))]

Thread 5 (Thread 0x7fdd8e826700 (LWP 1965)):
#0  0x00007fddaae418d9 in pthread_cond_timedwait@@GLIBC_2.3.2 () at /lib64/libpthread.so.0
#1  0x00007fddac8a20a6 in QWaitCondition::wait(QMutex*, unsigned long) () at /lib64/libQt5Core.so.5
#2  0x00007fddac89dc23 in QThreadPoolThread::run() () at /lib64/libQt5Core.so.5
#3  0x00007fddac8a0ede in QThreadPrivate::start(void*) () at /lib64/libQt5Core.so.5
#4  0x00007fddaae3c555 in start_thread () at /lib64/libpthread.so.0
#5  0x00007fddab597f3d in clone () at /lib64/libc.so.6

Thread 4 (Thread 0x7fdd8dc80700 (LWP 1972)):
#0  0x00007fddab58e3d3 in select () at /lib64/libc.so.6
#1  0x00007fddacad2dcf in qt_safe_select(int, fd_set*, fd_set*, fd_set*, timespec const*) () at /lib64/libQt5Core.so.5
#2  0x00007fddacad48ce in QEventDispatcherUNIXPrivate::doSelect(QFlags<QEventLoop::ProcessEventsFlag>, timespec*) () at /lib64/libQt5Core.so.5
#3  0x00007fddacad4dfe in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib64/libQt5Core.so.5
#4  0x00007fddaca7da8a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib64/libQt5Core.so.5
#5  0x00007fddac89bff4 in QThread::exec() () at /lib64/libQt5Core.so.5
#6  0x00007fddb2ffb935 in QQmlThreadPrivate::run() () at /lib64/libQt5Qml.so.5
#7  0x00007fddac8a0ede in QThreadPrivate::start(void*) () at /lib64/libQt5Core.so.5
#8  0x00007fddaae3c555 in start_thread () at /lib64/libpthread.so.0
#9  0x00007fddab597f3d in clone () at /lib64/libc.so.6

Thread 3 (Thread 0x7fdd86a4b700 (LWP 1988)):
#0  0x00007fddaae418d9 in pthread_cond_timedwait@@GLIBC_2.3.2 () at /lib64/libpthread.so.0
#1  0x00007fddac8a20a6 in QWaitCondition::wait(QMutex*, unsigned long) () at /lib64/libQt5Core.so.5
#2  0x00007fddac89dc23 in QThreadPoolThread::run() () at /lib64/libQt5Core.so.5
#3  0x00007fddac8a0ede in QThreadPrivate::start(void*) () at /lib64/libQt5Core.so.5
#4  0x00007fddaae3c555 in start_thread () at /lib64/libpthread.so.0
#5  0x00007fddab597f3d in clone () at /lib64/libc.so.6

Thread 2 (Thread 0x7fdd860e7700 (LWP 1993)):
#0  0x00007fddaae41530 in pthread_cond_wait@@GLIBC_2.3.2 () at /lib64/libpthread.so.0
#1  0x00007fddb41b46d4 in QTWTF::TCMalloc_PageHeap::scavengerThread() () at /lib64/libQt5Script.so.5
#2  0x00007fddb41b4719 in  () at /lib64/libQt5Script.so.5
#3  0x00007fddaae3c555 in start_thread () at /lib64/libpthread.so.0
#4  0x00007fddab597f3d in clone () at /lib64/libc.so.6

Thread 1 (Thread 0x7fddb53e3900 (LWP 1940)):
[KCrash Handler]
#5  0x00007fdd8c8958ab in gen7_update_renderbuffer_surface () at /usr/lib64/dri/i965_dri.so
#6  0x00007fdd8c8826ed in brw_update_renderbuffer_surfaces () at /usr/lib64/dri/i965_dri.so
#7  0x00007fdd8c862420 in brw_upload_state () at /usr/lib64/dri/i965_dri.so
#8  0x00007fdd8c7f68ba in brw_draw_prims () at /usr/lib64/dri/i965_dri.so
#9  0x00007fdd8c65750c in vbo_draw_arrays () at /usr/lib64/dri/i965_dri.so
#10 0x00007fddaeefa264 in KWin::GLVertexBuffer::draw(QRegion const&, unsigned int, int, int, bool) () at /lib64/libkwinglutils.so.6
#11 0x00007fddaeefe069 in KWin::GLVertexBuffer::render(QRegion const&, unsigned int, bool) () at /lib64/libkwinglutils.so.6
#12 0x00007fddaeefe0fa in KWin::GLVertexBuffer::render(unsigned int) () at /lib64/libkwinglutils.so.6
#13 0x00007fddb4d15e9a in KWin::SceneOpenGL2::doPaintBackground(QVector<float> const&) () at /lib64/libkwin.so.5
#14 0x00007fddb4d1a935 in KWin::SceneOpenGL::paintBackground(QRegion) () at /lib64/libkwin.so.5
#15 0x00007fddb4d04058 in KWin::Scene::paintSimpleScreen(int, QRegion) () at /lib64/libkwin.so.5
#16 0x00007fddb4d15bf3 in KWin::SceneOpenGL2::paintSimpleScreen(int, QRegion) () at /lib64/libkwin.so.5
#17 0x00007fddb4cfd724 in KWin::Scene::finalPaintScreen(int, QRegion, KWin::ScreenPaintData&) () at /lib64/libkwin.so.5
#18 0x00007fddb4d3902f in KWin::EffectsHandlerImpl::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /lib64/libkwin.so.5
#19 0x00007fddb49da51f in KWin::Effect::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /lib64/libkwineffects.so.6
#20 0x00007fddb4d38fda in KWin::EffectsHandlerImpl::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /lib64/libkwin.so.5
#21 0x00007fddb49da51f in KWin::Effect::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /lib64/libkwineffects.so.6
#22 0x00007fddb4d38fda in KWin::EffectsHandlerImpl::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /lib64/libkwin.so.5
#23 0x00007fddb49da51f in KWin::Effect::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /lib64/libkwineffects.so.6
#24 0x00007fddb4d38fda in KWin::EffectsHandlerImpl::paintScreen(int, QRegion, KWin::ScreenPaintData&) () at /lib64/libkwin.so.5
#25 0x00007fddb4cfd346 in KWin::Scene::paintScreen(int*, QRegion const&, QRegion const&, QRegion*, QRegion*) () at /lib64/libkwin.so.5
#26 0x00007fddb4d1b5e7 in KWin::SceneOpenGL::paint(QRegion, QList<KWin::Toplevel*>) () at /lib64/libkwin.so.5
#27 0x00007fddb4cf41c5 in KWin::Compositor::performCompositing() () at /lib64/libkwin.so.5
#28 0x00007fddacab1ac3 in QObject::event(QEvent*) () at /lib64/libQt5Core.so.5
#29 0x00007fddad7417cc in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /lib64/libQt5Widgets.so.5
#30 0x00007fddad746e70 in QApplication::notify(QObject*, QEvent*) () at /lib64/libQt5Widgets.so.5
#31 0x00007fddaca8024b in QCoreApplication::notifyInternal(QObject*, QEvent*) () at /lib64/libQt5Core.so.5
#32 0x00007fddacad655d in QTimerInfoList::activateTimers() () at /lib64/libQt5Core.so.5
#33 0x00007fddacad4d76 in QEventDispatcherUNIX::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib64/libQt5Core.so.5
#34 0x00007fdd9634e97d in QUnixEventDispatcherQPA::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib64/qt5/plugins/platforms/libqxcb.so
#35 0x00007fddaca7da8a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib64/libQt5Core.so.5
#36 0x00007fddaca855fc in QCoreApplication::exec() () at /lib64/libQt5Core.so.5
#37 0x00007fddb5065967 in kdemain () at /lib64/libkdeinit5_kwin_x11.so
#38 0x00007fddab4b6790 in __libc_start_main () at /lib64/libc.so.6
#39 0x0000000000400bc9 in _start ()

Reported using DrKonqi